Take a full readback from a working, factory-fresh device of the same model, same region (Global/China/India), and same board revision.
| Error | Likely cause | Fix | |-------|--------------|-----| | “Invalid IMEI” | NVRAM corrupted or wiped | Rewrite IMEI with SN Writer | | WiFi/BT address all zeros | NVRAM region partially overwritten | Restore nvdata backup | | NVRAM warning on boot | Checksum mismatch | Write original IMEI to fix checksum | | Maui META can’t connect | Driver or USB mode issue | Reinstall MTK VCOM driver, try different USB port | mt6768 nvram file